抗高血压药物对SHR大鼠主动脉DNA合成速率的研究

The Impact of Antihypertensive Drugs on DNA Synthetic Rate of Aorta \;Smooth Muscle Cell in SHR

目的通过抗高血压药物卡托普利及可乐宁治疗，对自发性高血压大鼠（ＳＨＲ）的主动脉平滑肌ＤＮＡ合成速率的影响，探讨药物治疗对大血管的作用。方法雄性ＳＨＲ，１２周龄，体重１３０ｇ～１５０ｇ，４２只随机分为３组，ａ．高血压对照组；ｂ．卡托普利组，给予小剂量卡托普利２０ｍｇ／ｋｇｄ－１；ｃ．可乐宁组，９只，给予可乐宁３０μｇ／ｋｇｄ－１。正常血压对照组ＷＫＹ，雄性８只，体重１５０ｇ～１８０ｇ；实验组给药１２周。观察指标：（１）收缩压（ＳＢＰ）自１２周起每４周一次，至２４周；（２）组织形态学方法观察主动脉壁腔比；（３）ＤＮＡ合成速率测定，蛋白、ＤＮＡ含量及与组织之比的影响。结果卡托普利治疗组和可乐宁治疗组均能明显抑制血压升高，并一定程度减轻血管壁肥厚，卡托普利治疗组ＤＮＡ合成速率显著下降（与ＳＨＲ相比Ｐ＜０．０１），蛋白／组织、ＤＮＡ／组织之比也有明显降低（均比ＳＨＲ降低，Ｐ＜０．０５）。可乐宁治疗组ＤＮＡ合成速率虽有所降低，但与ＳＨＲ相比无统计学差异，其它指标也无明显改变。血压与ＤＮＡ合成速率之间存在相关性ｒ＝０．４１９１．Ｐ＞０．０５。结论可乐宁和小剂量的卡托普利治疗ＳＨＲ，可以明显防止其高血压的发展。卡托普利可以?

Aim \ To explore the effect of captopril and clonidine on the DNA synthetic rate of aortic smooth muscle cell of spontaneously hypertensive rats.\ Methods \ 12 wk old male SHRs (BW 130 g150 g, n=42) were divided into 3 groups , each received captopril 20 mg/kg d-1, clonidine 30 g/kg d-1, and placebo for 12 weeks, respectively. Nomortensive WKY rats served as control (n=8, BW: 150 g180 g). During treatment, systolic blood pressure was measured every 4 weeks. Then rats were killed, lumen to wall ratio in aorta was analyzed by morphological methods. Smooth muscle cells were cultured. DNA synthetic rate, concentration of protein and DNA, protein/tissue ratio,and DNA/tissue rate were determined.\ Results \ Captopril and clonidine effectively reduced blood pressure and the wall thickening in SHR, DNA synthetic rate, DNA/tissue, and protein/tissue ratio were decreased in captopril treated SHR. All these index were not significantly affected by clonidine. DNA synthetic rate was correlated with SBP in SHR.\ Conclusion Clonidine and small dose of captopril prevented the development of hypertension in SHR. Captopril,but not clonidine, inhibited DNA synthetic rate in SMC of aorta in SHR.